I have two category dropdowns, the first for the parent categories and the second for the child categories. They form a chain so that when you select the parent category the second dropdown will be populated with its child categories. Here's the code in the form itself:

I'll only get the parent category saved for the post. How on earth can I have the parent AND the child categories both saved? Bear in mind that only one category should be selected from each dropdown, no multiples.

Yeah, by no means it's polished. Thanks for the suggestions, will use them down the line. What about the category problem though? I've understood you can only have one "value" in $_POST['main_cat'], so no 'main_cat','sub_cat', etc. I get error from them anyway.
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AndrewJul 5 '12 at 16:00